Redshift distribution in the Spiderweb field. Upper panel: distribution of all the 161 spectroscopic redshifts measured in the field. Lower panel: redshift distribution in the range 2.0 < z < 2.3. Vertical dashed lines show the redshift of the Spiderweb Galaxy as measured with low resolution spectroscopy by van Ojik (1995) (black line), the range adopted to define the Spiderweb Complex (magenta lines) and the protocluster (green lines), as discussed in the text.